1.Max Sound Output: 126 ± 4dB
2.Max Gain: 50 ± 5
3.Harmonic Wave Distortion: ≤ 8% (AT 1000 Hz)
4.Input Noise: ≤ 28 dB
5.Frequency Range: 300Hz ~ 4000Hz
6.Working Voltage: 1.5V
7.Working Current: ≤ 6.8 mA 8.Battery: AG13 or A675
* Hearing aid coil sensitivity >100dB